Various fixes & improvements
- chore: Bump mypy and fix abstract ContextManager typing (1421) by sl0thentr0py
- chore(issues): add link to Sentry support (1420) by vladanpaunovic
- fix: replace git.io links with redirect targets (1412) by asottile-sentry
- ref: Update error verbose for sentry init (1361) by targhs
- fix(sessions): Update session also for non sampled events and change filter order (1394) by adinauer